package com.adamjwh.pratice.offer;

import com.adamjwh.tools.TreeNode;

/**
 * 输入两棵二叉树A，B，判断B是不是A的子结构。（ps：我们约定空树不是任意一个树的子结构）
 */
public class JudgeSubTree {
    public boolean HasSubtree(TreeNode root1,TreeNode root2) {
        if(root1 == null || root2 == null) {
            return false;
        }

        return isSubtree(root1, root2) || isSubtree(root1.left, root2) || isSubtree(root1.right, root2);
    }

    public boolean isSubtree(TreeNode root1, TreeNode root2) {
        if(root2 == null) {
            return true;
        }

        if(root1 == null) {
            return false;
        }

        if(root1.val == root2.val) {
            return isSubtree(root1.left, root2.left) && isSubtree(root1.right, root2.right);
        } else {
            return false;
        }
    }

}
